1. Field of the Invention
This invention relates to an information terminal having a foldable structure.
2. Description of the Related Background Art
Portable information terminals of wireless communications systems for transmitting/receiving information have become very popular in recent years. Portable information terminals include those of portable telephone systems and personal handyphone systems (PHS) (hereinafter referred to as portable telephone sets).
FIG. 1 of the accompanying drawings shows a known portable telephone set comprising a housing 51 having a display section 50, another housing 53 having a key input section 52 and a hinge section 54, the housings 51 and 53 being adapted to be foldable relative to each other and put together.
Thus, such a portable telephone set becomes very small and hence easy to carry when it is not in use and the housings 51 and 53 are folded. Additionally, when the housings are folded, the display section 50 is protected against damage and the input section 52 is prevented from erroneous key operations.
When, on the other hand, the housings 51 and 53 are opened from each other by an appropriate angle for use, the microphone 55 and the loudspeaker of the portable telephone set become separated from each other by a distance corresponding to the distance between the mouth and one of the ears of the user to make the portable telephone set very comfortable for talking with the person at the other end of the line.
The display section 50 of the portable telephone set is used to display not only information on the ongoing telephone call but also information on unattended calls, the current condition of radio-wave propagation and so on that has to be seen frequently by the user.
Then, the housings 51 and 53 of the foldable type portable telephone set have to be opened to expose the display section 50 each time the user wants to see the information of the latter category. Therefore, a portable telephone set having a transparent viewing window 57 arranged on the housing 53 as illustrated in FIG. 2 has been proposed to avoid the cumbersome operation of opening the housings 51 and 53 and to allow the user to see information without opening them.
Meanwhile, there is a strong demand for portable telephone sets provided with various sophisticated features of information terminals such as a large memory capacity for storing telephone numbers and other data and the capability of transmitting/receiving character data. Then, such a sophisticated portable telephone set is adapted to display on the display section 50 various character data such as the telephone number and name of a person to be stored in the memory or a written message received or to be transmitted by electronic mail.
However, the viewing window 57 arranged on the housing 53 of a portable telephone set has to be subjected to certain limitations in terms of position and area because the key input section contains mechanical contacts and occupies a considerable space. In other words, the viewing window 57 is forced to be small relative to the display section 50 so that the visibility of the display section 50 is not fully guaranteed by the viewing window 57.
If the area of the viewing window 57 is enlarged to improve the visibility of the information displayed on the display section 50, the intervals separating the button keys and/or the sizes of the button keys of the key input section 52 have to be reduced at the cost of the operability of the portable telephone set.
The display section 50 of known portable telephone sets is often not large enough for displaying all the character data received by way of the character transmission service of the telephone system at a time. Then, the display section 50 has to be provided with a scroll feature. In short, the display section 50 of conventional portable telephone sets is not large enough for dealing with the amount of character data normally processed at a time in the portable telephone set.
In view of the above described circumstances, it is therefore the object of the present invention to provide an information terminal comprising a first housing having a display section and a second housing having an input/display section that are adapted to be folded relative to each other to make the portable telephone set very small that is excellent in terms of operability for inputting character data and has a capability of displaying a large volume of data.
According to the invention, the above object is achieved by providing an information terminal comprising a first housing having a display section for displaying information and a second housing having an input/display section for inputting and/or displaying information, said first and second housings being linked by a hinge mechanism fitted to an end of each of them so as to allow them to be folded relative to each other with said input/display section and said display section facing each other.
An information terminal according to the invention and having the above described configuration can be made very small when the first and second housing are folded relative to each other. Additionally, the information terminal provides excellent visibility and operability because the input/display section operates both as information input means and information display means.